SIP12401

SiP12401 Vishay Siliconix Boost Controller For Double AA Cell or Li-Ion Battery For White LED Application DESCRIPTION SiP12401 is a boost controller IC for double cell NiMH or Alkaline battery and Li Ion battery, which can drive white LEDs connected in series to provide backlight in hand-held devices. Series connection of the LEDs provides identical LED currents resulting in uniform brightness and eliminating the need for ballast resistors. For best efficiency performance, the SiP12401 is designed to operate in PWM mode with 600 kHz switching. The voltage-mode PWM design is internally compensated, reducing the external parts count. It accepts input voltages from 1.8 V to 5.0 V. The LED current can be adjusted externally for its brightness control. SiP12401 features low shutdown current of under 1 µA. SiP12401 is available in a lead (Pb)-free 6-pin, PowerPAK MLP33 package and is specified to operate over the industrial temperature range of - 40 °C to 85 °C. FEATURES • Voltage Mode Control with Internal Frequency Compensation • 1.8 V to 5.0 V Input Voltage Range • PWM Control with 600 kHz Fixed Switching Frequency • Analog Control of LED Intensity • Regulated Output Current • Integrated UVLO and Soft-Start • Logic Controlled Shutdown (< 1 µA) • High Efficiency: Typical 80 % • PowerPAK® MLP33-6 Package RoHS COMPLIANT APPLICATIONS • • • • • White LED Backlighting LCD Bias Supplies Handheld Devices Digital Cameras Portable Applications TYPICAL APPLICATION CIRCUIT MBR0520 VIN 22 µH 10 µF 2 VIN XSHD 1 XSHD AGND 4 4.7 µF SiP12401 3 FB PGND 5 15 Ω 6 EXT Si2302ADS Document Number: 73193 S-71822-Rev. C, 03-Sep-07 www.vishay.com 1 SiP12401 Vishay Siliconix ABSOLUTE MAXIMUM RATINGS (all voltages referenced to GND = 0 V) Parameter Input Voltage, VIN EXT Voltage XSHD Voltage FB Voltage Maximum Junction Temperature Storage Temperature Operating Junction Temperature Power Dissipationa Thermal Resistance b Limit - 0.3 to 6 - 0.3 to VIN + 0.5 - 0.3 to VIN + 0.5 - 0.3 to VIN + 0.5 150 - 55 to 150 125 PowerPAK MLP33-6 (TA = 70 °C)a PowerPAK MLP33-6 1100 50 Unit V °C mW °C/W Notes: a. Derate 20 mW/°C above 70 °C. b. Device Mounted with all leads soldered or welded to PC board. Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. RECOMMENDED OPERATING RANGE (all voltages referenced to GND = 0 V) Parameter Input Voltage, VIN XSHD, EXT Voltage LX Voltage FB Voltage Operating Temperature Range Limit 1.8 to 5 0 V to VIN 0 to VOUT + 0.5 0 to 5 - 40 to 85 °C V Unit SPECIFICATIONSa Parameter Input Voltage UVLO UVLO Hysteresis Feedback Voltage Feedback Input Current Maximum PWM Duty Cycle PWM Switching Frequency Quiescent Current Stand-By Current XSHD Input High Level XSHD Input Low Level EXT High On Resistance EXT Low On Resistance Symbol VIN VUVLO VUVLOHYST VFB IFB MAXDTY fOSC IQ ISTB VXSHDH VXSHDL REXTH REXTL IEXT = 10 mA VFB = 0.4 V XSHD = 0 V Full Full Full 35 30 1.2 0.2 Full VFB = 0.3 V 77 425 0.291 Full 0.282 1 85 600 200 775 300 1 Test Conditions Unless Specified VIN = 3 V, TA = 25 °C Limits Temp Full Full a Min 1.8 b Typc 1.65 0.1 0.3 Maxb 5 1.77 Unit V 0.309 0.318 nA % kHz µA V Ω Notes: a. Full = - 40 to 85 °C. b. The algebraic convention whereby the most negative value is a minimum and the most positive a maximum (- 40° to 85 °C). c. Typical values are for DESIGN AID ONLY, not guaranteed nor subject to production testing. www.vishay.com 2 Document Number: 73193 S-71822-Rev. C, 03-Sep-07 SiP12401 Vishay Siliconix PIN CONFIGURATION AND TRUTH TABLE PowerPAK MLP33-6 XSHD 1 6 EXT VIN 2 5 PGND FB 3 4 AGND Top View ORDERING INFORMATION Part Number SiP12401DMP-T1-E3 Temperature Range - 40 to 85 °C Marking 2401 PIN DESCRIPTION Pin Number 1 2 3 4 5 6 Name XSDH VIN FB AGND PGND EXT Battery Input Voltage Output Voltage Feedback Pin Signal Ground Power Ground Drive Pin for External Power MOS Function Logic Controlled Shutdown Input, XSHD = High: Normal Operation, XSHD = Low: Shutdown PIN FUNCTIONS XSHD (Pin 1) XSHD is the logic controlled shutdown input pin. When XSHD is low, the IC is shutdown and it’s quiescent current is less than 1 µA. When XSHD is high, the IC is working in normal operation. VIN (Pin 2) VIN is the pin connected to battery input voltage. The IC gets its power supply from VIN. FB (Pin 3) FB is the feedback pin of the output voltage via resistor divider. FB is about 0.3 V and its difference from 0.3 V reference voltage is amplified by the error amplifier. AGND (Pin 4) AGND is the pin for ground of controlling circuit. PGND (Pin 5) PGND is the pin for ground of the internal power MOS driver. EXT (Pin 6) EXT is the output pin of internal driver. It’s connected to the gate of external power MOSFET. Document Number: 73193 S-71822-Rev. C, 03-Sep-07 www.vishay.com 3 SiP12401 Vishay Siliconix FUNCTIONAL BLOCK DIAGRAM VIN AGND Compensation FB E/A + + PWM - Driver EXT PGND XSHD Reference and Soft-Start Oscillator DETAILED OPERATION SiP12401 is a 600 kHz boost controller IC, packaged in 6-pin MLP33, for white LED applications. It features fixed frequency voltage mode PWM control with internal frequency compensation. With the low rDS(on) external power MOSFET, this device maintains high efficiency over a wide range of load current. Soft-Start During soft-start, the loop compensation guarantees the slow increase of the output voltage and inrush current, so that no large voltage overshoot and inrush current occur when the soft-start is ended. PWM operation After soft-start, the device is working in PWM operation with a fixed frequency of 600 kHz. APPLICATION INFORMATION White LED Brightness Control The current of white LED can be adjusted by PWM signal on the XSHD pin or by a variable dc voltage to control its brightness, (see Figure 1.) As control voltage VCTRL increases, the voltage drop on R2 increases and the voltage drop on R1 decreases. Thus, the LED current decreases. The selection of R2 and R3 will make the current from VCTRL much smaller than LED current and much larger than the FB pin bias current. MBR0520 VIN 22 µH 10 µF 2 VIN XSHD 1 XSHD AGND 4 4.7 µF ILED 0.3 V 15 Ω 0.3 - V CTRL 15 Ω R2 R3 3 FB SiP12401 6 EXT PGND 5 Si2302ADS R2 1 kΩ R3 3.9 kΩ 15 Ω VCTRL www.vishay.com 4 Document Number: 73193 S-71822-Rev. C, 03-Sep-07 SiP12401 Vishay Siliconix TYPICAL CHARACTERISTICS 85 220 215 84 Supply Curremt (mA) 210 205 200 195 190 81 185 80 - 50 180 - 50 % Duty Cycle 83 82 - 30 - 10 10 30 50 70 90 - 30 - 10 10 30 50 70 90 Temperature (°C) Temperature (°C) Maximum PWM Duty Cycle vs. Temperature 4 3 1.0 Feedback Voltage Accuracy (%) 2 1 VIN = 5 V 0 -1 -2 -3 -4 - 50 0.2 VIN = 2 V Shutdown Threshold (V) 1.2 Supply Current vs. Temperature VIN = 5 V 0.8 VIN = 2 V 0.6 0.4 - 30 - 10 10 30 50 70 90 0.0 - 50 - 30 - 10 10 30 50 70 90 Temperature (°C) Temperature (°C) Feedback Voltage vs. Temperature Shutdown Threshold vs. Temperature Document Number: 73193 S-71822-Rev. C, 03-Sep-07 www.vishay.com 5 SiP12401 Vishay Siliconix TYPICAL WAVEFORMS VXSHD 2 V/div VIN 20 mV/div ac coupled VOUT 50 mV/div ac coupled VOUT 2 V/div VFB 0.2 V/div VEXT 2 V/div VIN = 3.6 V Four LEDs in series 1 ms/div 1 µs/div Figure 1. PWM Dimming Control 200 Hz 50 % Duty Cycle PWM Signal on XSHD Pin Figure 3. Switching Waveforms: VIN, VOUT and VEXT VIN = 3.6 V, L = 22 µH, COUT = 4.7 µF, Four LEDs in Series Vishay Siliconix maintains worldwide manufacturing capability. Products may be manufactured at one of several qualified locations. Reliability data for Silicon Technology and Package Reliability represent a composite of all qualified locations. For related documents such as package/tape drawings, part marking, and reliability data, see http://www.vishay.com/ppg?73193. www.vishay.com 6 Document Number: 73193 S-71822-Rev. C, 03-Sep-07 Legal Disclaimer Notice Vishay Disclaimer All product specifications and data are subject to change without notice. Vishay Intertechnology, Inc., its affiliates, agents, and employees, and all persons acting on its or their behalf (collectively, “Vishay”), disclaim any and all liability for any errors, inaccuracies or incompleteness contained herein or in any other disclosure relating to any product. Vishay disclaims any and all liability arising out of the use or application of any product described herein or of any information provided herein to the maximum extent permitted by law. The product specifications do not expand or otherwise modify Vishay’s terms and conditions of purchase, including but not limited to the warranty expressed therein, which apply to these products. No license, express or implied, by estoppel or otherwise, to any intellectual property rights is granted by this document or by any conduct of Vishay. The products shown herein are not designed for use in medical, life-saving, or life-sustaining applications unless otherwise expressly indicated. Customers using or selling Vishay products not expressly indicated for use in such applications do so entirely at their own risk and agree to fully indemnify Vishay for any damages arising or resulting from such use or sale. Please contact authorized Vishay personnel to obtain written terms and conditions regarding products designed for such applications. Product names and markings noted herein may be trademarks of their respective owners. Document Number: 91000 Revision: 18-Jul-08 www.vishay.com 1